ARM: LPC32xx: Added lpc32xx_defconfig

This patch adds a working defconfig for the LPC32XX architecture. It is a
general default configuration for the PHY3250 reference board and others
based on LPC32XX.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Kevin Wells <kevin.wells@nxp.com>
Signed-off-by: Olof Johansson <olof@lixom.net>